Heating unit



July 10, 1962 1.. c. HANSON 3,043,944

HEATING UNIT Filed June 10, 1959 2 Sheets-Sheet 1 jg 5 I I I, I v

July 10, 1962 L. c. HANSON 3,

HEATING UNIT Filed June 10, 1959 r 2 Sheets-Sheet 2 Jfi 19 a? 4 23 fir z/iz for:

zeroy C flazzsozz 40 5% United States Patent 3,043,944 HEATING UNIT Leroy C. Hanson, Elmhurst, Ill., assignor to Form Corporation, a corporation of Ohio Filed June 10, 1952, Ser. No. 819,310 12 Claims. (Cl. 219-37) This invention relates to a heating unit and more particularly to a heating unit particularly adapted for use in a counter-top type of electric stove.

It is the general object of the present invention to produce a new and improved heating unit of the character described.

It is a more specific object of the invention to produce a heating unit including a spillage pan having an Outer lip adapted to be supported by the edges of an opening in the counter, wherein the terminal block for the electrical connections of the unit is secured on the pan below the lip portion so that the same may be mounted in a minimum space both as regards width and depth.

Another object of the invention is to produce a heating unit of the character described in the preceding paragraph wherein the terminal blook is secured to a thin sheet-like bracket which is welded to the outer surface of the spillage pan and has a portion spaced from said surface defining an insulating air space above the terminal block.

A further object of the invention is the provision of a heating unit including a spillage pan having a wall a heating unit in which a coil heating element is mounted on a carrier which has a locking portion engageable with a surface of the spillage pan, the carrier being resiliently held in place as by forces exerted by resilient female terminals and the resilient coils of the heating element.

Still a further object is the provision of cooperating guide surfaces on the coil assembly and terminal block for limiting and directing the movement of the coil terminals into engagement with the terminals in the terminal block. More specifically, a finger on the coil assembly extends into a recess in the terminal block and surfaces I at the top and bottom of the recess limit the movement of and guide the coil assembly upon its insertion and removal. One of the guide surfaces serves as a ground connection for the coil assembly.

Other and further objects and advantages of the invention will be readily apparent from the following description and drawings, in which:

FIGURE 1 is a top plan view of a heating unit en bodying the invention;

FIGURE 2. is a side elevational view of the apparatus shown in FIGURE 1;

FIGURE 3 is a vertical section taken along the line 3-3 of FIGURE 1;

FIGURE 4 is a vertical section taken along the line 44 of FIGURE 1;

FIGURE 5 is an enlarged vertical section taken along the line 5-5 of FIGURE 4;

FIGURE 6 is an enlarged horizontal section taken along line 6-6 of FIGURE 4; and

FIGURE 7 is a vertical section taken along line 77 of FIGURE 6.

While this invention is susceptible of embodiments in many ditferent forms, there is shown in the drawings and will herein be described in detail one specific em 3,043,944 Patented July 10, 1962 bodiment, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiment illustrated. The scope of the invention will be pointed out in the appended claims.

Referring now to the drawings there is shown a heating unit' 10 including a pan 11 having a central dished portion 12 and an outer lip portion 13 terminating in an outer circular edge 14. A heating coil 15 is secured by means not shown) to a three legged carrier or bracket 16 lying within the dished portion 12 and removably supported in place therein by engagement of the ends 17 of the arms of carrier 16 on supporting surfaces 18 inwardly indented in the wall 12a of the pan. As will appear more fully below, a finger 17a at the end of one of the support arms 16 locks under a detent 18a above one of the supporting surfaces 18 (-FIGURE 4).

Spillage pan 12 is mounted in an opening 19 in a suitable counter-like cooking surface 20, as of stainless or enameled steel. Spring clips 21 secured to the outer surface of spillage pan 12 hold the pan heating unit in place, yet permit removal as may be necessary, for cleaning or the like.

The ends 22 and 23 of heating coil 15 extend through a metal plate 24, which serves as a grease guard and terrninate in male contact portions 25 and 26. The male contacts are separably engageablewith female contacts carried by terminal block 27, for energization of the heating element.

Terminal block 27, which may be of Bakelite or other heat resistant insulating material, is arranged according to the present invention to lie beneath lip portion 13 of the spillage pan 12 and preferably substantially completely within the confines of the outer edge 14 so that the unit may easily be inserted in counter opening 15 of minimum size. Terminal block 27 has mounted therein a pair of springy female terminals 28 and 29 which are accessible through openings 30 and 31 formed in a portion 32 of the terminal block which extends through an opening 34 formed in the wall 12a of the pan. If desired, blade-type contacts with wiping female terminals may be substituted for the terminals shown in the drawing.

Terminal block 27 is preferably mounted against the outer surface of the wall of thepan on a bracket 36 spot welded to the pan and to the undersurface of lip portion 13 in a manner providing a space 37 between the confronting surfaces of the bracket and the lip portion as indicated in FIGURES 4 and 7. The terminal block is secured to the bracket 36 by screws 38 which extend through the bracket and terminate in a space 34, thus avoiding any discontinuity or holes in the lip portion and securely mounting the terminal block in the desired position. The air space between bracket 36 and lip 13 acts as an insulator and prevents excessive radiation of heat from the element 15 to terminal block 27. Of course,

other mounting arrangements may be utilized, as by screwing the terminal block directly to the wall of the pan.

A pair of binding screws 39 and 40 are provided for the female terminals 28 and 29, respectively, and face outwardly of the terminal block facilitating connection with a suitable source of electricity. These connections may be made after the unit is installed in a cooking surface, if the under portion of the surface is relatively open, or may be made before installation of the unit Where the underside of the cooking surface is enclosed.

Terminal guide openings 30 and 31 in block 27 are larger than male coil terminals 25 and 26 so that the terminals have a loose fit therein. A guide finger 42 extends outwardly from grease guard 24, between male terminals 25 and 26. A recess 43 is provided in terminal block 27 to receive finger 4?. and to guide the movement of male terminals 25 and 26 upon insertion and removal. A pair of guide surfaces 44 and 4-5 are provided above and below recess 43 to aid in guiding movement of the coil assembly. Both guide surfaces preferably have curved end portions to facilitate insertion of guide finger 42, and the surface M- is formed as a part of the wall of spillage pan 12. The lower guide surface 45 has an extension 45a secured to terminal block 27 and provided with a binding screw 46. Surface 45 engages the lower edge of guide finger 42 when the unit is fully inserted and serves to ground the heating unit through a suitable grounded connection to binding screw :6.

Latching finger 17a on coil support 16 is held in engagement with latching detent 1351 by a combination of two forces. The first force is provided by the resiliency of female contacts 23 and 29 acting against the ends of male contacts 25 and 26. The second force results from deformation of coiled heating element 15 upon insertion of the heating element assembly into spill pan 12.

The heating element may be removed from the pan by forcing the carrier in to the right as shown in FIG- URE 4, against the resiliency of the female contacts and the coil itself, releasing locking portion 17a from detent 18a. The left portion of the assembly is lifted, rocking male contacts 25 and 26 in oversize openings 35) and 31 to a position in which the carrier may be moved to the left over the top of ring 13. The unit may then be lifted out freeing the male contacts from the terminal block.

The bottom 50 of pan 11 is provided with an outer bottom element 51, spaced therefrom and secured thereto at a central region 52 as shown. The double-bottom construction provides insulation preventing excessive heat radiation downwardly below the spillage pan and adds strength and rigidity to the unit. The reduction in downward heat radiation permits installation of the unit in a cooking surface which has only a shallow space below it, as excessive heating of the space beneath is prevented. Furthermore, the fixed mounting of the terminal block on the wall of the pan and, for the most part, beneath trim ring 1 3 permits installation of the unit in a space much smaller than that required by most such units.

I claim:

1. A heating unit for a counter-top type stove comprising a spillage pan having a central dished portion and an outer lip portion terminating in an outer circular edge, a thin sheet-like bracket entirely within the confines of said lip and the adjacent outer surface of the dished portion, said bracket being secured at its edges to the outside surface of the dished portion beneath the lip portion with an intermediate portion of the bracket bridging across the under surface of the lip portion to provide an air space between said pan and bracket, a terminal block mounted on said bracket lying substantially directly beneath the lateral extent of the lip and substantially above the lower extent of the pan secured to the bracket by securing means extending through the bracket and terminating in said space, a pair of female contact portions on the terminal block, and a heating coil positioned Within the pan and provided with male contact portions located to be inserted in said female contact portions.

2. A heating unit for a counter-top type stove, comprising a spillage pan with a trim ring extending outwardly and downwardly therefrom, a terminal block mounted on said pan lying substantially directly beneath the lateral extent of the ring and substantially above the lower extent of the pan, a plate element extending transversely above the top of the terminal block and below said trim ring, said plate element terminating inside the lateral extent of the trim ring and spaced from said trim ring to define an insulating air space above the terminal block, a pair of female contact portions on the terminal block, and a heating coil positioned within the pan and provided with male contact portions engaged with said female contact portions.

3. A heating unit for a counter-top type stove, comprising a spillage pan having a wall portion with a trim ring extending outwardly from the upper edge thereof, a terminal block mounted substantially directly beneath the lateral extent of the ring and substantially above the lower extent of the pan and against said wall portion and having terminal guide portions extending through said Wall, a pair of female contact portions carried on said terminal block and operably associated with said guide portions, and a heating coil positioned within the pan and provided with male contact portions engaged with said female contact portions, said coil having a guard plate mounted thereon adjacent the male contact portions and removably engaging only the inner surface of said pan adjacent said terminal guide portions to shield the contact portions from spillage.

4. A heating unit for a counter-top type stove, comprising a spillage pan having a wall portion with a trim ring extending outwardly from the upper edge thereof, said wall portion having .a downwardly facing locking surface projecting inwardly therefrom, a terminal block mounted outside said pan at a location opposite to said locking surface, resilient female terminals on said block and accessible through the wall of said pan, an electrical heating element of resilient material formed in a coil having male terminals engaged with said female terminals and said block, and a carrier having a lock portion for engagement with said locking surface and having extensions extending transversely to a line between said block and said locking surface, said heating element being secured over and to said carrier to enable forces exerted on said male terminals by the block and said resilient female terminals to urge the lock portion against the locking surface.

5. A heating unit for a counter-top type stove, comprising a spillage pan having a wall portion with a trim ring extending outwardly from the upper edge thereof, said wall portion having a. downwardly facing locking surface projecting inwardly therefrom, a terminal block mounted outside said pan at a location opposite to said locking surface and havin" terminal neck portions extending through said wall portion, resilient female terminals on said block and accessible through said neck portions, an electrical heating element disposed above said neck portions and having male terminals engaged with said female terminals and said neck portions, and a carrier having a lock portion for engagement with said locking surface and having extensions extending transversely of a line between said block and locking surface, said heating element being secured over and to said carrier to enable forces exerted on said male terminals by the neck portions to resiliently bend the coil slightly across the carrier extensions to bring the lock portion against the locking surface.

6. A heating unit for a counter-top type stove, comprising a spillage pan having a wall portion with a trim ring extending outwardly from the upper edge thereof, said wall portion having a downwardly facing locking surface projecting inwardly therefrom, a terminal block mounted outside said pan at a location opposite said locking surface resilient female terminals on said block and accessible through said neck portion, an electrical heating element being secured thereto and of resilient material formed in a coil having male terminals engaged with said female terminals, .a carrier for said coil element having a lock portion engaged with said locking surface, the carrier lock portion being held in place by force exerted by the resilient terminals.

7. A heating unit for a counter-top type stove comprising: a spillage pan, a terminal block mounted on said pan having female contact portions facing inwardly thereof and a guide recess formed therein, a heating coil positioned within the pan provided with-male contact portions located to be inserted in the female contact portions of said block and having a guide finger extending slightly outwardly beyond said male contact portions to enter said recess prior to entrance of the male contact portions into the female contact portions, and surfaces adjacent said recess guiding the insertion and removal of the guide finger.

8. The heating unit of claim 7, wherein said surfaces are at the top and bottom of said recess and are rounded.

9. A heating unit for a counter-top type stove comprising a spillage pan, a terminal block mounted on said pan having female contact portions facing inwardly thereof and a guide recess formed therein, a heating coil positioned within the pan provided with male contact portions located to be inserted in the female contact portions of said block and having a guide finger extending slightly outwardly beyond said male contact portions to enter said recess prior to entrance of the male contact portions into the female portions, and surfaces adjacent said recess for guiding the insertion and removal of the guide finger, and a ground connection to one of said surfaces.

10. In a counter-top type stove, an electrical heating unit adapted for recessed mounting within a stove plate of said counter-top, comprising: a shallow pan having a continuous side wall adapted to fit closely within an aperture of said stove plate and a continuous lip extending outwardly and downwardly from the pans upper edge to form an air pocket between said stove plate and pan; an elongated bracket within the confines of said lip and adjacent said side wall, said bracket bridging between the underside of said lip and said side wall to form a reduced air pocket thereabove and along the extent of said bracket; a terminal block mounted on said bracket and interrupting the margin of said stove plate lying beneath said bracket, said bracket lying substantially directly beneath the lateral extent of said lip; a pair of female contact portions on the terminal block; and a heating coil positioned within the pan and provided with male contact portions engaged with said female contact portions.

11. An electrical heating unit as in claim 10, in which said pan sidewall has spaced apart and horizontally aligned supporting surfaces projecting slightly inwardly from the inner surface thereof and a downwardly facing locking surface above the supporting surfaces projecting inwardly from the inner side of the pan, said terminal block being mounted on said bracket at a position on the pan opposite to said locking surface, said block having resilient female contact portions facing inwardly and neck portions extending through said side wall with guide openings to provide access to the female contact portions, said heating coil being of a flexible resilient material having straight ends each with a male contact portion for engaging both said female contact portions and the sides of said neck portions and including a support for said heating coil seated on said pan support surfaces having extensions extending transversely to a line between said block and said locking surface, said support having a locking portion adapted to engage said locking surface,

said heating coil being secured to said support to enable forces exerted on said coil ends by the terminal block and the resilient female contact portions to urge the locking portion of said support into engagement with said locking surface.

12. In a counter-top type stove, an electrical heating unit adapted to be mounted on a stove plate of the countertop in recessed position relative thereto, comprising: a shallow pan having a continuous side wall adapted to fit closely within an aperture of said stove plate and a continuous lip extending outwardly and downwardly from its upper edge to overlay the adjacent margin of the stove plate and form an air pocket therebetween, said pan side wall having spaced apart and horizontally aligned. supporting surfaces projecting slightly inwardly from the inner surface thereof and a downwardly facing locking surface above the supporting surface and projecting slightly inwardly from the inner side of said pan sidewall; a

bracket adapted to fit within the confines of said lip and adjacent said side wall to extend horizontally therealong, said bracket bridging the underside of said lip and said sidewall to form a reduced air pocket thereabove and along the extent of said bracket; a terminal block mounted on said bracket and interrupting the margin of said stove plate located beneath said bracket, said terminal block being positioned on the opposite side of said pan from the locking surface and lying substantially directly beneath the lateral extent of the lip and substantially above the lower extent of the pan, said block having spaced apart resilient female contact portions facing inwardly thereof and a guide recess formed intermediate the female contact portions, said block having terminal neck portions extending through said side wall and having guide openings to provide access to the said female contact portions; a heating coil of flexible resilient material provided in the pan having straight ends each with a male contact portion for engaging said female contact portions and the neck portions of said block, said coil having a plate mounted on said ends adapted to fit the contour of the inner side of said pan sidewall above and below the area through whichsaid ends pass, said plate having a guide finger extending slightly outwardly beyond said male contact portions, to enter said recess prior to entrance of the male contact portions into said neck portions; guide surfaces on said block and adjacent said recess to guide the insertion and removal of the guide finger; and a support for said heating coils seated on said support surfaces of the pan having extensions extending transversely to a line between said block and said locking surface, said support having a locking portion adapted to engage said locking surface, said heating coil being secured to said support to enable forces exerted on said coil ends by the terminal block and the resilient female contact portions to urge the locking portion of said support into tight engagement with said locking surface.

References Cited in the file of this patent UNITED STATES PATENTS 2,414,667 Price Jan. 21, 1947 2,565,443 Vogel et a1 Aug. 21, 1951 2,790,062 McOrlly Apr. 23, 1957 2,923,802 Price Feb. 2, 1960 FOREIGN PATENTS 562,300 Canada Aug. 26, 1958 

